I’d attempt to refinance to bring down payment. 

You have to determine what your goals are and then attempt to achieve them.

Find character references for them after the meeting. 

In this case, because you have a relationship with the seller, I would suggest either telling them of your plans to wholesale it OR attempting to find a buyer FIRST before you put the lot under contract.

Im a young person striving to invest and I got curious about the character of my future wife.

Your response was not helpful and only serves as a blight attempt to bash others. 

I am chatting with him on Monday, but attempting to do some due diligence prior to speaking with him.

You are doing your research here in an attempt to verify the value.If you get a plethora of people you believe to indicated that they believed it was worth the cost then maybe it is.  

Window AC is not the best because the property has the original windows, and most window units aren't made for historic windows with storms over them.I want to preserve the character of the property, so smaller units mounted in the ceiling will be the least noticeable.

There are other posts on here about the sponsor that you can attempt to reach others who may have invested in this fund.2.